Marked progress has been made on a special microscope-microspectrophotometer. It has been possible to isolate single modal patterns in rod receptors of frogs and rats for study by passing light through the retina. Initial optical studies of cone receptors will be undertaken shortly, and an effort will be made to complete the electronics of the instrument in the coming year. A new Stiles-Crawford apparatus has been completed. It has been possible to show that retinal receptors across the human retina are aligned with a point approximating the center of the exit pupil of the eye. Now, emphasis is shifting towards an analysis of the factors affecting receptor orientation and the possible recovery of alignment after retinal pathology, etc. The relationship between fovea receptor orientation and interferometrically determined retinal resolution will be reinvestigated. Clinically, studies of a psychophysical function believed to reflect retinal receptive field properties will be pursued. An effort will be made to clarify changes occurring in this function in glaucoma. Attempts will be made to further localize its response components. Central foveal changes in the Westheimer function will be correlated with interferometrically determined resolution, the modulation transfer function, and acuity. The complex behavior described as a short term saturation or visual fatigue-like effect will also be studied in greater detail in individuals exhibiting visual pathway lesions.